Article of Apparel

ABSTRACT

The present invention is directed toward an article of apparel effective to regulate the temperature of the wearer. In an embodiment, the article of apparel includes a base textile with a thermal regulation membrane. The thermal regulation membrane contains a plurality of system-reactive components selectively engaged heat and/or moisture. In an embodiment, the printed coating includes a cooling agent, a phase change material, and a heat dissipation material. In operation, the article of apparel is effective to delay/diminish the rise in skin temperature (compared to a garment lacking the membrane), increasing wearer comfort.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority to provisional application No.61/886,835, filed 4 Oct. 2013 and entitled “Article of Apparel withCooling Features,” the disclosure of which is hereby incorporated byreference in its entirety.

FIELD OF THE INVENTION

The present invention is directed to an article of apparel, inparticular, with an article of apparel with comfort regulationproperties.

BACKGROUND OF THE INVENTION

Athletes generate heat as a result of physical activity—skin and/or corebody temperature rise during sustained physical exertion. Failure toproperly move heat away from the body during exercise may lead to“overheating,” i.e., a rise in the core body temperature, potentiallyresulting in adverse health consequences, such as heat exhaustion orheat stroke. Accordingly, performance apparel may be configured to aidin the regulation of body temperature, with its aim being to keep thewearer cool. One approach configures a garment such that it drawsmoisture away from the skin. Other approaches equip the garment withtubes through which a cooling fluid flows, while still others providethe garment with pockets that receive cooling packs of variousmaterials. These conventional approaches, however, suffer fromdisadvantages. Absorbent material, while increasing the comfort of thewearer, does not facilitate absorbing of heat. Cooling tubes and packs,while effective cooling mechanisms, add significant weight to thegarment.

Thus, it would be desirable to provide a lightweight article of appareleffective to cool and/or temper the increase in temperature of the user.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed toward an article of apparel includinga base textile with a comfort regulation membrane. The comfortregulation membrane contains a plurality of system-reactive componentsselectively engaged heat and/or moisture. In an embodiment, the printedcoating includes a cooling agent, a phase change material, and a heatdissipation material. The system reactive components may be provided inparticulate form, being suspended in a binder. In operation, the articleof apparel is effective to delay/diminish the rise in skin temperature(compared to a garment lacking the membrane) and/or improve the overallmoisture management capacity of the substrate, either of which mayimprove wearer comfort.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 illustrates a front view in elevation of an article of apparelincluding a thermal regulation membrane in accordance with an embodimentof the invention;

FIG. 2 illustrates a schematic of an apparatus for applying the thermalregulation membrane to the substrate;

FIG. 3 illustrates an application pattern of the thermal regulationmembrane in accordance with an embodiment of the invention;

FIG. 4 illustrates the application pattern of FIG. 3, shown in an array;

FIGS. 5A, 5B, and 5C illustrate the process wherein an apparatus appliesheat and pressure to a coated substrate to integrate the thermalregulation apparel with the substrate;

FIG. 6 illustrates a flow diagram of the process of forming the articleof apparel; and

FIGS. 7A and 7B illustrate the application pattern of FIG. 4 applied tothe interior surface of an article of apparel, with the patterns shownin a smaller (FIG. 7A) and larger (FIG. 7B) scale.

Like reference numerals have been used to identify like elementsthroughout this disclosure.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, an article of apparel 100 includes a base textileor substrate 105 with an inner surface 110 that faces (contacts) thewearer and an outer surface 115 that faces away from the wearer. Thesubstrate 105 is a fabric (e.g., a woven, knitted, or non-woven fabric)including natural and/or synthetic yarns. By way of example, the yarnsmay be formed of nylon, polyester, rayon, cotton, elastane, wool, silk,or a blend thereof. The substrate 105 can be treated with dyes,colorants, pigments, UV absorbers, plasticizers, lubricants, flameinhibitors, rheology agents, etc., either before or thereafterapplication of the thermal regulation membrane.

The substrate 105 may be constructed to have one or more desiredproperties such as air permeability, absorbance, moisture vaportransmission, and/or capillary action (to draw sweat away from thewearer), abrasion resistance, anti-static properties, anti-microbialactivity, water repellence, flame repellence, hydrophilicity,hydrophobicity, wind resistance, UV protection, resiliency, stainresistance, wrinkle resistance, etc. In a preferred embodiment, thesubstrate is breathable, possessing an air permeability of at least 50cfm, preferably greater than 70 cfm. By way of example, the substratemay possess an air permeability of about 75 cfm—about 205 cfm.

The substrate 105 forms at least a portion of the article of apparel100. The article of apparel includes, but is not limited to, athleticwear such as compression garments, shirts, shorts, pants, headwear(e.g., headbands), outerwear (e.g., jackets, hats, gloves), footwear(e.g., shoes, boots, slippers), sleepwear, and undergarments. In theembodiment of FIG. 1, the article of apparel is a compression shirtincluding arms 120A, 120B and a torso 130. In the figure, the shirt isprovided with a cut-away section 135 to reveal the apparel inner surface110.

A comfort or thermal regulation membrane or layer 150 is disposed on theinner substrate surface 115. The thermal regulation membrane 150 iseffective to alter the temperature regulation and/or moisture managementproperties of the substrate 105. Accordingly, the thermal regulationmembrane 150 contains one or more system reactive components. By systemreactive, it is intended to mean a compound that reacts to environmentalconditions within a system. That is, the system reactive materials areselectively engaged in response to conditions of a wearer wearing thearticle of apparel. In particular, the compound absorbs, directs, and/ormitigates fluid (heat or water) depending on existing system conditions.For example, a component may initiate an endothermic reaction (e.g.,when exposed to water). By way of further example, a component may becapable of selectively absorbing and releasing thermal energy (heat). Byway of still further example, a component may be capable or conductingand/or directing heat from one location to another location within asystem.

In an embodiment, the system reactive components include a coolingagent, a latent heat agent, and/or a heat dissipation agent. The coolingagent is an endothermic cooling agent, i.e., it creates a system thatabsorbs heat. Specifically, the cooling agent generates an endothermicreaction in aqueous solution, absorbing energy from its surroundings.Accordingly, the cooling agent possesses a negative heat of solutionwhen dissolved in water. By way of example, the endothermic coolingagent possesses a heat of enthalpy in the range −10 cal/g to −50 cal/g.In particular, the endothermic cooling agent possesses a heat ofenthalpy in the range −20 cal/g to −40 cal/g. With this configuration,when the cooling agent is contacted by water (i.e., the sweat of thewearer), the cooling agent is capable of cooling (i.e., lowering thetemperature of) the water.

The cooling agent may be a polyol. By way of example, the cooling agentincludes one or more of erythritol, lactitol, maltitol, mannitol,sorbitol, and xylitol. In an embodiment, the cooling agent is selectedfrom one or more of sorbitol, xylitol and erythritol. Sorbitol is ahexavalent sugar alcohol and is derived from the catalytic reduction ofglucose. Xylitol is produced by catalytic hydrogenation of thepentahydric alcohol xylose. Erythritol is produced from glucose byfermentation with yeast. Crystalline xylitol is preferred. The coolingagent may be present in an amount of about 15 wt % to about 35 wt %(e.g., about 25 wt %).

The latent heat agent is capable of absorbing and releasing thermalenergy from a system while maintaining a generally constant temperature.In an embodiment, the latent heat agent is a phase change material(PCM). Phase change materials possess the ability to change state(solid, liquid, or vapor) within a specified temperature range. PCMsabsorb heat energy from the environment when exposed to a temperaturebeyond a threshold value, and release heat to the environment once thetemperature falls below the threshold value. For example, when the PCMis a solid-liquid PCM, the material begins as a solid. As thetemperature rises, the PCM absorbs heat, storing this energy andbecoming liquefied. Conversely, when temperature falls, the PCM releasesthe stored heat energy and crystallizes or solidifies. The overalltemperature of the PCM during the storage and release of heat remainsgenerally constant.

The phase change material should possess good thermal conductivity(enabling it to store or release heat in a short amount of time), a highstorage density (enabling it to store a sufficient amount of heat), andthe ability to oscillate between solid-liquid phases for a predeterminedamount of time. Additionally, the phase change material should melt andsolidify at a narrow temperature range to ensure rapid thermal response.

Linear chain hydrocarbons are suitable for use as the phase changematerials. Linear chain hydrocarbons having a melting point andcrystallization point falling within approximately 10° C. to 40° C.(e.g., 15° C. to 35° C.) and a latent heat of approximately 175 to 250J/g (e.g., 185 to 240 J/g) may be utilized. In particular, a paraffinlinear chain hydrocarbon having 15-20 carbon atoms may be utilized. Themelting and crystallization temperatures of paraffin linear chainhydrocarbons having 15-20 carbon atoms fall in the range from 10° C. to37° C. and 12° C.-30° C., respectively. The phase transition temperatureof linear chain hydrocarbons, moreover, is dependent on the number ofcarbon atoms in the chain. By selecting a chain with a specified numberof carbon atoms, a material can be selected such that its phasetransition temperature liquefies and solidifies within a specifiedtemperature window. For example, the phase change material may beselected to change phase at a temperature near (e.g., 1° C.-5° C. aboveor below) the average skin temperature of a user (i.e., a human wearerof the apparel, e.g., 33° C.-34° C.). With this configuration, the phasechange material begins to regulate temperature either upon placement ofthe apparel on the wearer or shortly after the wearer begins physicalactivity.

In an embodiment, the paraffin is encapsulated in a polymer shell.Encapsulation prevents leakage of the phase change material in itsliquid phase, as well as protects the material during processing (e.g.,application to the substrate) and during consumer use. The resultingmicrocapsules may possess a diameter of about 1 to about 500 μm. In anembodiment, the paraffin PCM is present in an amount of about 25 wt % toabout 45 wt % (e.g., about 35 wt %).

The heat dissipation agent is effective to conduct heat and/or directheat from one location to another location within the system (e.g.,within the membrane 150 and/or substrate 105). In an embodiment, theheat dissipation agent possesses a high heat capacity, which determineshow much the temperature of the agent will rise relative to the amountof heat applied. By way of example, the heat dissipation agent is asilicate mineral such as jade, e.g., nephrite, jadeite, or combinationsthereof. The heat dissipation material may be present in an amount (dryformulation) of about 30 wt % to about 50 wt % (e.g., about 40 wt %).

The system reactive components are present with respect to each other ina ratio of approximately 1:1 to 1:2. By way of example, the ratio oftemperature reactive components—cooling agent, latent heat agent, andheat dissipation agent—may be approximately 1:2:2, respectively. Asindicated above, in system reactive component mixture, the cooling agentis present in an amount of from 15 wt % to 35 wt %; the latent heatagent is present in an amount of from 25 wt % to 45 wt %. Similarly, theheat dissipation agent is present in an amount of from 25 wt % to 45 wt%.

In addition to the temperature reactive components, the thermalregulation membrane 150 further includes a binder effective to dispersethe temperature reactive components and/or to adhere the temperaturereactive components to the substrate 105 (e.g., to the yarns/fibersforming the substrate). The binder may be an elastomeric materialpossessing good elongation and tensile strength properties. Elastomericmaterials typically have chains with high flexibility and lowintermolecular interactions and either physical or chemical crosslinksto prevent flow of chains past one another when a material is stressed.In an embodiment, polyurethane (e.g., thermoplastic polyurethane such aspolyester-based polyurethane) is utilized as the binder. In otherembodiments, block copolymers with hard and soft segments may beutilized. For example, styrenic block copolymers such as astyrene-ethylene/butylene-styrene (SEBS) block copolymer may beutilized.

The comfort regulation membrane 150 is applied to the substrate 105 in amanner that maintains the integrity of the components and preservesproperties of the substrate. In an embodiment, the thermal regulationmembrane is applied as a composition transferred to the substrate viaprinting process. By way of example, the composition is transferred viaa rotogravure apparatus 200. Referring to FIG. 2, the rotogravureapparatus 200 includes an impression roller 205, a gravure or etchedcylinder 210, and a tank 215. The cylinder 210 is engraved/etched withrecessed surface cells in a desired pattern (pattern not illustrated inFIG. 2). The tank 215 holds the thermal regulation composition 220. Theapparatus 200 further includes a doctor blade 225 operable to removeexcess composition from the cylinder 210.

In an embodiment, the comfort regulation composition 220 includes about20 wt % system reactive components (the cooling agent, the latent heatagent, and the phase change material), 30 wt % binder, and about 50 wt %solvent (aqueous or non-aqueous (e.g., methyl ethyl ketone)). In otherembodiments, the thermal regulation composition may further includepigments or other additives such as surfactants.

In operation, as the cylinder 210 rotates, a portion of the cylinderbecomes immersed in the thermal regulation composition 220 stored in thetank 215. The composition 220 coats the cylinder 210, becoming capturedwithin the cells. The cylinder continues to rotate, moving the coatedcylinder past the doctor blade 225, which removes excess composition 220from the cylinder 210. The substrate 105 is directed between theimpression roller 205 and the cylinder 210 such that the inner surface110 of the substrate (e.g., what will be the wearer-facing side of theapparel) contacts the cylinder 210. Specifically, the impression roller205 applies force to the substrate 105, pressing the substrate onto thecylinder 210, thereby ensuring even and maximum coverage of the thermalregulation composition 220. Surface tension forces pull the composition220 out of the cells, transferring it to the substrate 105. Accordingly,the rotogravure apparatus 200 applies an initial or first pressure tothe substrate 105 at an initial or first temperature (e.g., ambienttemperature) to transfer the thermal regulation composition 220 to thesubstrate surface 115. Once the composition 220 is transferred, thecoated substrate may pass through one or more heaters to evaporate thesolvent, thereby drying the composition and forming the dry membranelayer 150. If a thicker membrane is desired, additional passes throughthe rotogravure apparatus 200 may be completed.

The thermal regulation composition 220 may be applied to the substrate105 in any pattern suitable for its described purpose. In an embodiment,the thermal regulation membrane 150 is applied in a repeating pattern ofunits. Referring to FIG. 3, each unit 300 includes generally linearelements 305 oriented in spaced relationship from each other, beingseparated by element channels 310 such that adjacent elements areoriented generally parallel to each other. The dimensions of each linearmember 305 and channel 310 may be any suitable for its describedpurpose.

The linear members 305 are organized such that a discontinuous array ofelements spans the substrate surface 110. In the illustrated embodiment,the linear members 305 are organized such that they cooperate to definea first or outer triangular section 315A and a second or innertriangular section 315B. The first triangular section 315A is a mirrorimage of the second triangular section 315B, and vice versa. Thetriangle sections 315A, 315B, in turn, cooperate to define a quadrant orsubstructure 317 of the unit 300. Each quadrant 317 is intersected byone or more (e.g., five) radial channels 320, as well as a segmentchannel 325 that separates the first triangle section 315A from thesecond triangle section 315B. The radial 320 and segment 325 channelsmay possess a wider transverse dimension than the element channels 310.The substructures 310, moreover, cooperate to define a central aperture330 disposed the center of the structure 300.

Referring to FIG. 4, a plurality of units 300 are disposed adjacent eachother form a pattern 400 on the substrate. Specifically, the units 300are oriented in rows 405 and columns 410 along the substrate 110 suchthat a network of interconnecting channels is formed. With thisconfiguration, the linear members 305 represent areas along thesubstrate including (covered by) the thermal regulation membrane 150.The channels 310, 320, 325 and apertures 330 in contrast, define areasfree (e.g., substantially free) of the thermal regulation membrane 150.The areas covered by the thermal regulation membrane 150 modify theproperties of the substrate 105 by providing increased (improved)temperature regulation properties to the substrate (compared to an areafree of membrane). The substrate properties in the areas free of thethermal regulation membrane, in contrast, are not modified. This createsa bimodal surface in which the properties of the substrate 105 (e.g.,air permeability, vapor transmission, etc.) and the properties of themembrane 150 cooperate to provide the article of apparel 100 withdesired properties (explained in greater detail below). Stated anotherway, the each unit 300 of the pattern 400 may include a ratio of freearea to treated area falling within predetermined values. By way ofexample, the ratio of free area to covered area may be approximately 3:1(i.e., the treated area covers approximately 30% of the substratesurface 115).

After drying, the coated substrate 105 is processed to further integratethe membrane 150 into the fibers/yarns of the substrate. In anembodiment, the coated substrate 150 is subjected to a second pressureand temperature different from the temperature and pressure appliedduring the rotogravure process. In particular, the coated substrate 150is subjected to a calendaring process in which the coated substrate ispassed between a pair of heated rollers. The temperature of the rollers(and thus the temperature applied to a substrate surface (coated ornon-coated)) may range from about 25° C. to about 55° C. Temperaturesabove this range cause puckering in the fabric (e.g., along thepatterned areas). Temperatures below this range are generallyinsufficient to improve the hand of the fabric. In a preferredembodiment, the substrate 105 (e.g., the coated surface 115) iscalendared at a temperature of approximately 30° C. The pressure appliedto the substrate by the rollers ranges from about 30-70 lbs, with about50 lbs being preferred. Pressures above this range risk rupturing thePCM material, while pressures below this range are insufficient to pressthe membrane into fabric cavities. The speed at which the fabric passesthrough the calendaring apparatus may be in the range of about 300-400rpm, with about 350 rpm being preferred.

The above calendaring process not only improves the hand of the coatedsubstrate, but also integrates the thermal regulation membrane 150 intothe substrate 105. Referring to FIGS. 5A, 5B, and 5C, a coated substrate500 includes the substrate 105 with the thermal regulation membrane 150disposed on inner substrate surface 110 (while shown to be a continuouslayer, it should be understood that the thermal regulation membrane maybe discontinuous). The coated substrate 500 is drawn through thecalendaring rollers 520A, 520B (FIG. 5B). As explained above, therollers 520A, 520B apply heat and pressure to the substrate 105 andmembrane 150, urging at least a portion of the membrane below thesubstrate surface 110. It is believed that the membrane binder softens,permitting the membrane 150 to enter into the openings between thefibers and/or coat the fibers of the substrate 105. Alternatively, theheat and pressure may soften the substrate fibers, increasing therelative movement of the fibers, thereby creating openings in thetextile that receive the membrane 150. Regardless, calendaring mayresult in yarns/fibers intersecting (e.g., protruding from) the membrane150 and/or may result in the membrane coating/enveloping individualfibers along (e.g., below) the interface 110. As shown (FIG. 5C), aftercalendaring, the membrane 150 is pressed into the substrate 105 (beyondinitial substrate surface 515), becoming integrated therewith.

By way of further explanation, it is believed that composition andprocessing result in a porous or semi-porous membrane including pores orpockets formed therein. That is, the high ratio of system reactivecomponent particles to binder—as well as the compression of the membrane150 into the substrate 105—may create fissure, pores, or cavities withinthe membrane. These pores/cavities may be effective to transportingwater within the system. Specifically, the membrane 150 may transportwater away from the skin of the wearer and into the pores/cavities,where one or more of the system reactive components are located. Thus,when fluid is drawn toward the cooling agent, the agent may absorb waterto generate the endothermic reaction. Alternatively, the water maybecome trapped in a cavity within the membrane, or pass completelythrough the membrane to the substrate 105. Accordingly, in addition totempering the temperature within the system, the membrane 150 furtherimproves the overall moisture management capacity of the substrate 105compared to an untreated substrate (discussed in greater detail below).

The process of forming the article of apparel is explained withreference to FIG. 6. The process 600 begins at Step 605, with thesubstrate 105 being obtained. As explained above, the substrate 105 maybe woven, non-woven, or knitted, and may possess predeterminedproperties falling within specified ranges (air permeability, fluidmovement, etc.). By way of example, the substrate 105 is a four-waystretch fabric including polyester and elastane fibers. In Step 610, thethermal regulation coating is obtained. By way of example, approximately25 wt % crystalline xylitol, approximately 40 wt % jade particles, andapproximately 35 wt % encapsulated paraffin is mixed to form a systemreactive component mixture (dry mixture). The system reactive componentmixture is combined with solvent (methyl ethyl ketone) and binder(polyurethane) to form the thermal regulation composition 220. Theresulting composition includes approximately 20 wt % system reactiveagent (approximate 5 wt % xylitol, 8 wt %, jade, 7 wt % PCM insolution), approximately 30 wt % binder, with the remainder solvent(approximately 50 wt %).

In Step 615, the thermal regulation composition 220 is applied to thesurface 110 (the wearer-facing surface) of the substrate 105 at a firsttemperature and pressure in the manner explained above (viarotogravure). Once applied, at Step 620, the coating is dried (e.g., viaheating), thereby forming the thermal regulation membrane 150. In step625, the substrate 105 is processed at a second temperature andpressure. In particular, the coated substrate is calendared as explainedabove (roller temperature 30° C. at 50 lbs pressure and roll speed of350 rpm). Finally, the coated and calendared substrate 105 may beintegrated into an article of apparel in Step 630. By way of example,the substrate may be treated like conventional fabric, being cut andsewn to form a desired garment.

Referring to FIG. 7, the substrate 105 may form a compression shirt. Thepattern 400 may be modified to provide the desired level of coverage.For example, the scale and/or density of the pattern may be modified.For example, the embodiment of FIG. 7A possesses a high density pattern,which covers more surface area of the substrate than the low densitypattern of FIG. 7B. As explained above, the desired level of coverage isup to about 30% of the surface area of the substrate 105. That it, whenthe thermal regulation member 150 is applied to the substrate 105, thesurface area of the substrate surface 115 covered by the membrane isapproximately 30% or less.

The resulting thermal regulation membrane 150 is effective to improvethe thermal comfort of a wearer. In particular, the thermal regulationmembrane is effective to either delay the increase of skin temperatureand/or maintain the skin temperature at a lower value compared to thesame substrate lacking the thermal regulation membrane.

Experimental I

Fourteen test subjects (male and female, ages 21-26, BMI 21-26)completed two trials, each including 45 minutes of interval running inan environmental chamber set to 35.5° C. and 54.5% relative humidity(heat index=43.2° C.). The environment was selected to provide anenvironment in which sweating (evaporative cooling) was the only coolingmechanism occurring (i.e., no radiation, no convection, and noconduction). The subjects were allowed unlimited water intake duringtheir experimental exercise sessions in order to maintain hydration.Environmental temperature and relative humidity were measured using adigital meter, while heat index was calculated using a standardequation. There were no significant differences among the conditions orover time. Accordingly, it was determined that a similar quantity ofheat stress was applied during each shirt condition.

The exercise protocol included intervals of different exercise stimulidesigned to elicit specific quantities of heat gain. Specifically, thetest subjects ran on a treadmill that, at intervals, was either set to alow speed (3.5 mph) or a high speed (5 mph). Seven intervals wereutilized, ranging from five minutes to 10 minutes. In the first trial,the test subjects wore a compression shirt having the thermal regulationmembrane 150 described above in reference to the process flow diagram(FIG. 6). In the second trial, test subjects work a compression shirtfree of the thermal regulation membrane 150. Thus, tests were run on thesame substrate, one provided with the membrane 150 (trial 1) and oneunprinted (trial 2). Skin temperature was measured via sensors andwireless data loggers set to record at regular intervals. Measurementswere taken along the front of the neck, underneath the article ofapparel 100 (a short-sleeved compression shirt).

The skin temperature measurements taken at five-minute intervals (fromtime=5 min to time=45 min, with temperatures of all users averaged) werelower for the test subjects wearing the treated article of apparel(trial 1) than for the test subjects wearing the untreated article ofapparel (trial 2) (skin temperature measurements taken at the same timeinterval, i.e., at the same point during the same physical activity). Inother words, the thermal regulation membrane 150 was effective to lessenthe increase of wearer skin temperature during physical activity. Themembrane tempered/modulated the increase. Thus, a user wearing thetreated shirt for a predetermined period of time would experience lowerskin temperatures for a predetermined period of time after commencementof activity. Reduced skin temperature is critical factor in user comfort(along with airflow, and vapor transfer).

While not being bound to theory, it is believed that the system reactivecomponents become active in stages, reacting to the environment (theinterface between the article of apparel 100 and the skin of thewearer). In particular, it is believed the heat dissipation agent isactive immediately upon placement onto a user. That is, heat generatedby the wearer (and escaping from wearer's skin) is conducted by the jadeand directed outward, through the substrate 105 to the ambientenvironment. When wearer temperature increases beyond the steady stateof the heat dissipation agent (such that the heat dissipation agent canno longer exhaust all the heat energy produced by the wearer), and whenthe temperature of the environment increases beyond the fusiontemperature of the phase change material, the latent heat agent becomesactive, absorbing heat energy and storing it while maintaining agenerally consistent temperature.

Additionally, when the temperature of the wearer increases, the body'sevaporative cooling response will activate, causing the body to sweat.Once exuded, the perspiration (water) will either contact a treated oruntreated area of the substrate 105. In untreated areas (i.e., areasfree of membrane 150), the perspiration will be pulled outward, awayfrom the skin via capillary action. In treated areas (i.e., areas coatedwith the thermal regulation membrane 150), the perspiration will contactthe endothermic cooling agent, generating an endothermic reaction andlowering the temperature of the water.

Additionally, as the skin temperature decreases, the latent heat agent(the phase change material) will reach its crystallization temperature,releasing the heat previously stored. The heat dissipation agent remainsactive, conducting the heat released by the latent heat agent anddirecting it outward (away from the wearer), through the substrate 105and into the surrounding environment.

Accordingly, the article of apparel is effective to dissipate heat notonly during heat-up (when the wearer's temperature is rising), but alsoduring cool down (when the wearer's temperature is lowering).

Experimental II

A substrate material including a knitted fabric of elastane andpolyester was treated thermal regulation membrane 150 described above inreference to the process flow diagram (FIG. 6). Additionally, a second,untreated substrate was obtained. Moisture management properties of thesubstrates were measured utilizing a moisture management tester andknown protocols (e.g., AATCC TM 195), including back and face wettingtime (second), back and face absorption rate (%/second), back and facewetted radius (millimeter), back and face spreading speed(millimeter/second), cumulative one way transport capacity, and overallmoisture management capacity (OMMC). The results are provided in TableI.

TABLE I Measurement Max Max (Measured at Wetting Wetting Wetted WettedSpreading One-Way Back or Face of Time- Time- Absorption AbsorptionRadius- Radius- Speed- Spreading Transport Substrate) Back FaceRate-Back Rate-Face Back Face Back Face Index OMMC units s s %/s %/s mmmm mm/sec mm/sec % Treated 5.80 5.74 54.1 64.2 20.8 25.8 3.06 3.36145.02 0.5387 Substrate Untreated 3.56 3.53 54.5 53.9 20.0 20.0 3.283.34 15.72 0.3904 Substrate

As shown, the overall moisture management capacity of the treatedsubstrate is significantly higher (closer to 1.0) than that of theuntreated substrate. Moisture management property is a key factor indetermining the comfort of the wearer—the wearer's perception ofmoisture is affected by the transmittance of moisture through thesubstrate. Thus, controlling the movement of moisture from the skin andto the atmosphere via the fabric is critical in improving user comfort.Here, the treated substrate possesses an improved overall moisturemanagement capacity relative to the untreated substrate. While not beingbound to a particular theory, it is believed the thermal regulationmembrane 150 may include cavities or pores as a result of theparticulate material and/or the softening/compression processing asexplained above. Accordingly, water from the wearer's skin is drawn intothe membrane 150, passing through the substrate 105, becoming capturedin a cavity, and/or interacting with a system reactive agent.

While the invention has been described in detail and with reference tospecific embodiments thereof, it will be apparent to one skilled in theart that various changes and modifications can be made therein withoutdeparting from the spirit and scope thereof. For example, the thermalregulation membrane 150 may be applied in a pattern or a continuous ordiscontinuous array. A discontinuous pattern has been found to providecooling to the user while still allowing the base fabric to performdesired properties (e.g., breathe and allow moisture vapor to escapethrough the fabric in order to reduce the level of moisture build up).While linear elements are illustrated, other shapes are possibleincluding circles, triangles, squares, pentagons, hexagons, octagons,stars, crosses, crescents, and/or ovals.

In an embodiment, the units 300 of the thermoregulation membrane 150 maybe arranged such that they are in connection with one another, such as alattice pattern or any other pattern that permits partial coverage ofthe substrate. For example, the composition may be disposed on thesubstrate 105 in a pattern with discontinuous elements and/orinterconnected geometrical patterns. In various embodiments, the pattern400 may be symmetrical, ordered, random, and/or asymmetrical. Moreover,the pattern 400 of thermal regulation membrane 150 may be disposed onthe substrate 105 at strategic locations to improve the performance ofthe article of apparel 100. In various embodiments, the size and/orspacing of the linear members 305 or units 300 may also be varied indifferent areas of the article of apparel to balance the need forenhanced cooling properties and preserve the functionality of thesubstrate.

While the invention has been described in detail and with reference tospecific embodiments thereof, it will be apparent to one skilled in theart that various changes and modifications can be made therein withoutdeparting from the spirit and scope thereof. Thus, it is intended thatthe present invention covers the modifications and variations of thisinvention provided they come within the scope of the appended claims andtheir equivalents. It is to be understood that terms such as “top”,“bottom”, “front”, “rear”, “side”, “height”, “length”, “width”, “upper”,“lower”, “interior”, “exterior”, and the like as may be used herein,merely describe points of reference and do not limit the presentinvention to any particular orientation or configuration.

We claim:
 1. An article of apparel comprising: a textile substrateincluding a first surface and a second surface opposite the firstsurface; and a thermal regulation membrane disposed on the firstsubstrate surface, the thermal regulation membrane comprising aplurality of system reactive components, the system reactive materialsbeing selectively engaged in response to conditions of a wearer wearingthe article of apparel.
 2. The article of apparel of claim 1, whereinthe system reactive components are selected from the group consisting ofa cooling agent, a latent heat agent, and a heat dissipation agent. 3.The article of apparel according to claim 1, wherein the plurality ofsystem reactive components include a cooling agent, a latent heat agent,and a heat dissipation agent.
 4. The article of apparel according toclaim 3, wherein: the cooling agent is a polyol selected from the groupconsisting of sorbitol, xylitol and erythritol; and the latent heatagent is a phase change material comprising a paraffinic hydrocarbon. 5.The article of apparel according to claim 4, wherein the heatdissipation agent comprises a silicate mineral.
 6. The article ofapparel according to claim 5, wherein the silicate material is jade. 7.The article of apparel according to claim 6, wherein the thermalregulation membrane further comprises a binder.
 8. The article ofapparel according to claim 7, wherein the binder is polyurethane.
 9. Thearticle of apparel according to claim 8, wherein the textile substrateis selected from the group consisting of a woven fabric, a knittedfabric, and a nonwoven fabric.
 10. The article of apparel according toclaim 9, wherein: the first surface is a wearer-facing surface of thearticle of apparel; and the article of apparel is oriented such that thefirst surface contacts the wearer.
 11. The article of apparel accordingto claim 10, wherein: the first substrate surface defines a surfacearea; and the thermal regulation membrane covers up to 30% of thesurface area of the first substrate surface.
 12. The article of apparelaccording to claim 11, wherein the thermal regulation membrane isdiscontinuous, thereby defining treated areas and untreated areas alongthe first substrate surface.
 13. A method of forming an article ofapparel, the method comprising: obtaining a textile substrate; applyinga thermal regulation composition to a surface of the textile substrateat a first temperature and a first pressure to form a coated textilesubstrate; drying the coated textile substrate to form a thermalregulation membrane disposed on the surface of the textile substrate;and compressing the substrate with the thermal regulation membrane at asecond pressure and a second temperature to position a portion of thethermal regulation membrane below the surface of the textile substrate;and incorporating the substrate into an article of apparel.
 14. Themethod of forming an article of apparel according to claim 13, whereinapplying comprises applying via a rotogravure apparatus.
 15. The methodof forming an article of apparel according to claim 14, wherein: thefirst pressure differs from the second pressure; and the firsttemperature differs from the second temperature.
 16. The method offorming an article of apparel according to claim 14, wherein: the secondtemperature is from 25° C. to 55° C.; and the second pressure is fromabout 30 to 70 lbs.
 17. The method of forming an article of apparelaccording to claim 16, wherein: the second temperature is about 30° C.;and the second pressure is about 50 lbs.
 18. The method of forming anarticle of apparel according to claim 13, wherein: applying comprisesapplying the thermal regulation composition in a discontinuous patternincluding a plurality of linear elements to form a bimodal substratesurface defining treated and untreated areas; and properties of theuntreated areas and the properties of the treated areas cooperate toprovide the article of apparel with temperature regulation properties.